Sxtrface-grinding machine



June 12, 1923. 1,458,623

C. KNOWLES SURFACE GRINDING MACHINE Filedflune 16 1920 5 Sheets-Sheet 1 June 12, 1923. 1,458,623

c. KNOWLES SURFACE GRINDING MACHINE Filedjune l6 1920 5 SheetsSheet 2 ma ma June 12, 1923.

C. KNOWLES SURFACE GRINDING MACHINE Filed Ju ne 16 1920 5 Sheets-Shebh 5 June 12, 1923. 1,458,623

C. KNOWLEFS SURFACE GRINDING MACHINE Filed June 16, 1920 5 Sheets-Sheet 4 m 012M tor June 12 1923; 1,458,623

a. KNOWLES SURFACE GRINDING MACHINE Filed June 16, 1920 5 Sheets-Sheet 5 r a [ll Q mum Patented June 12, 1923.

UNITED STATES PATENT OFFICE.

CARROLL KNOWLES, OF HARTFORD, CONNECTICUT, ASSIGNOE TO PRATT & \VHITNEY COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

SURFACE-GRINDING MACHINE.

Application filed June 16, 1920. Serial No. 389,431.

To all whom it may concern:

Be it known that I, CARROLL KNowLns, a citizen of the United States, residing at Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Surface- Grindi 1g Machines, of which the followin is a specification.

his invention relates to grinding machines of the surface type in which a wheel of abrading material is rapidly revolved, preferably about a vertical axis, and brought down into contact with the work to be ground mounted on a slowly revolving work table.

More particularly the invention relates to surface grinders in which an abrasive wheel of annular form engages the w rk to be ground against one of its flat end surfaces.

The objects of the present invention are to improve the construction of a surface grinding machine of the above type and in particular to improve the details of construction of the work table and operating means therefor.

More particularly, it is an object of the invention to mount a rotatable work table about a normally vertical axis which may be inclined or tilted slightly as, for instance, about a horizontal. axis so that the grinding machine may be utilized to grind a slightly concave or convex surface.

Another object is to so mount this table in combination with its driving means that the table may be revolved in one direction ahead of. or independently of, the driving mechanism so that while the table is being loaded with work preparation for the grinding operation, it may be easily rotated by hand to place the pieces or work to be ground in position on the work table.

Another object of the invention is to provide an improved guard surrounding and enclosing the wheel and work table so that the water used in connection with the abrasive wheel will not be thrown oil, but will be confined to a channel and returned to a storage tank conveniently provided on or near the machine.

This guard surrounding the wheel and the work table is preferably made in two pieces one of which is pivoted to the other so that a portion, as for instance the front portion, of the guard may be moved to an inoperative or lowered position to facilitate access to the work table to load and unload the pieces on the table.

A portion of the guard is preferably provided as an integral part of the carriage in which the work table is mounted, the rear portion of this guard being made considerably higher than its forward portion. To the rear portion of this guard. is pivoted the movable portion of the guard Normally the movable guard portion is held up in its operative position by a latch. When it is desired to place pieces to be ground on the table or to remove them after having been ground it is only necessary to operate the latch which causes the movable portion of the guard to fall. from its operative position to a position low enough to permit ready access to the work table by the operator.

Also it is an object of the invention to provide an improved adjusting or controlling means for varying the pressure oi the wheel against the work and to adjust and feed the wheel down toward, the work. this means also providing a convenient means vtor quickly lowering and raising the wheel into and out of contact with the work.

In the accompanying drawings, I have shown an embodiment oi the invention which I now deem preferable but it is to be understood that changes and modifications may be made within the scope of the appended claims without departing from the spirit of the invention.

In the drawings annexed hereto and forming a part herewith:

Figure 1. shows a side elevation of the complete machine, the outline of some of the principal parts being shown in dotted lines.

Fig. 2 is an enlarged elevational view, shown in cross section, of the abrasive wheel, wheel slide and spindle.

Fig. 8 is a cross sectional view in elevation of the work table and driving connections therefor.

Fig. 1 is an elevation in section of the main driving means and speed change mechanism for driving the table.

Fig. 5 is a view of the wheel slide adj usting and feeding means, parts of the same being shown in section.

Fig. 6 is a side view of the same.

Fig. 7 is another view showing the means for this regulating device.

Fig. 8 is a cross sectional view taken on line 8-8 of Fig. 3.

Fig. 9 is a view ofthe clutch shown in Fig. 8.

Fig. 10 is a detail view of the worlr table adjusting means.

Fig. 11 is a rear view of the wheel slide.

Fig. 12 is a sectional view of the wheel slide taken on line 12-12 of Fig. 2.

Fig. 13 is an outside view of a flexible joint provided in the table driving means.

The invention in its entirety comprises the following principal elements; namely, first abase or frame for the machine; second, a vertically slidable carriage having mounted at its lower end a grinding or abrasive wheel. adapted to be rapidly rotated about a vertical axis; third, a rotatable work table adapted to be rotated at different speeds much slower than the abrasive wheel and also mounted so that .its axis of rotation, which is normally vertical. may be tilted through a small angle out of parallelism with the axis of the grinding wheel; fourth, a. device for controlling the vertical movements of the grinding wheel and slide so that the wheel may be rapidly raised or lowered from or to the work, or very gradually lowered and fed toward the work; and fifth, a suitable enclosure or guard for the grinding wheel and table adapted to be quickly moved into and out of operative position to facilitate loading and unloading of the work table with articles to be ground.

Referring more particularly to the figures of the drawings, 10 refers to the base or frame of the surface grinding machine provided with a column 11 resting on the upper surface of the base 10. Preferably the column 11 is rigidly secured to the base 10, the securing means holding the column permanently in position perpendicularly to the upper surface of the base. The for ward vertical surface of the column 11 is-provided with vertical ways 12 by which a wheel slide 13 is accurately guided in its movements toward and, away from the work table 14 and held in sliding engagement with and in position against the column 11.

The wheel slide is clearly shown in Figs. 2, 11 and 12 and will now be described in detail. This wheel mounting or slide is in the form of a carriage 13 vertically slidable along suitable ways 12 provided on the column 11 as above stated. On the slide 13 is a suitable adjustable gib 15 fitting the ways 12 on the column 11 to constrain the slide to move vertically. Preferably, 1 secure adepending cover strip 13 to the lower edge of the slide 13 adjacent the ways 12. This is shown in Figs. 1 and 3 and serves to protect the ways 12 from exposure to the water used in connection with the grinding machine. Suitably fastened longitudinally to the rear of the slide 13 is a rack 16 adapted to engage a pinion 17 on a wheel adjusting shaft 18. Shaft 18 is rotatively mounted horizontally in the column 11. Centrally mounted in the slide 13 in an axis parallel to the ways 12 is the wheel spindle 20. This spindle or shaft 20 at its lower end has an abrasive wheel 21 detachably attached by means of. a flange member 22 suitably keyed or otherwise fastened to the lower end of shaft 20, the abrasive wheel 21 being locked in place by a locking plate Between this flange member 22 and locking plate 23 the wheel 21 is clamped or fastened by means of a cap screw 2 1 threaded into the lower end of spindle 20.

Directly surrounding the abrasive wheel 21 is a protective guard 27 depending from a ring 28 suitably fastened to the lower portion of the slide 13. Preferably the guard 27* can be adjusted relative to the ring 28" and be held firmly in adjusted position by a screw clamping means 29.

In order to permit rotation of this shaft 20 and the wheel 21 with a minimum of resistance, l ireferably mount it in suitable anti-friction bearings, one of which, as shown at 25, is in the form of a ballbearing near the lower end of the spindle 20 and. the other similar bearing 26 placed near the upper end of spindle 20.

The thrust of the spindle 20 while in operation is taken principally by the antifriction hearing: 25. I preferably support the spindle 20 in such a way presently to be described. that it is forced upward by suitable sprii'igs 34. When it is brought down into contact with the work there will be no lost mot-ion between the spindle 20 and slide 13 and consequently there willbe no tendency for the wheel to press against the work after downward feeding movement has been stopped.

The rotat-ive speed of the spindle 20 is so high that its bearii'lgs must be kept well lubricated and for this purpose 1 have provided an improved lubricating system in which a large amount of lubricant may be constantly circulated.

For this purpose I provide. an oil receptacle formed around the spindle 20. On the clamping plate 22 is formed an annular flange 27 so that between this flange 2'? ant the lower end of slide 13 an annular chainbcr is provided which may be supplied with lubricant through an opening The outer wall of the receptacle formed by the flange rotates with the spindle so that the oil is rapidly rotated and, due to the centrifugal force oi the rotating oil, oi-cod against the flange 27 at a high pressure. To aid in retaining the lubricant in its receptacle and to prevent its. flowingover the dance 27, this flange 27 is circumteren iiially or helically grooved as shown.

Depending from the lower surface of the slide 13 is a scoop-shaped member 29 dip ping into the oil receptacle above described. The scoop member 29 is connected with a tube 39 extending vertically upward pastsight aperture ill and connecting with a bore in the slide 13 extending to a point just above the anti-friction bei-iring 26.

Oil is driven into pipe 39 from the receptacle within the flange 27 by the momentum of the rotating oil and rises in tube 39 where it flows from tube 39 and passes through the ball bearing 26, thus lubricating it. Another tube ll extends trom below the antifriction bearing 26 down to a point d5 adjacent the spindle 20 and above toe antifriction bearing; 25. he oil atter passi o through bear 26 and tube al may then flow through bearing and back into the receptacle within flange 27.

The supporting means for the wheel spindle 20 comprises the following construction which designed to force the spindle upward against the thrust bearing portions of the anti-friction or ball bearing 25.

The upper portion of the wheel slide 11 is suitably bored. out, as shown at 30 the lower end oi this bore being closed by a flange 31 also bored to permit the passage of the wheel spindle 2O therethrough. The flange 3i is tastened to the lower end or": the bored out section 30 by cap screws 011th ing within the bored out section 30 is a. inenil'ier 33 containing a plurality of helical springs 34-, their lower ends resting against the 'lltlllg'l'e or ring: 31 and each being; partly countersunk into the member or block 3 The outer ringof the ball-bearing; 26 rests on the upper surface of this member and is so fitted that t may slide easily Within the bored out section 30. At the top of the slide 11 a cover plate suitably fasten d to the slide by cap screws Preferably the members 35 and 33 are provided with overlappine,- parts. as shown, to prevent dust from entering hearing; 26.

(in the slide 20 the inner ring: of the ball bearing 26 is held in place by suitable washers 87. 3'4 and a locking nut forcing thi ring against a shoulder provided on spindle 20. t ecured to the spindle 20, preferably between wasl rs Ta? and 37, l place a shedder or battle to aid in preventing the lubricant from escaping past the washer or sleeve 3"? and out ot the slide Preferably the washer or sleeve 37 grooved circumferen tiallv or helically, also to aid in retaining the luluicant in place. M will be seen from ti above construction that the weight oil? i I and the pressure of springs 3 1 lieu up by the ballbearing 26 when wheel is out oi? contact with the work but that as soon as it is pressed against the .lT the thrust is taken up by the lower l aring which is made larger and on to take up this upward pressure. .e cringe previously mentioned. are .tlt resiliency to balance the weight v are always held in their uppermost pomotion to be taken up by the adjusteeatng means for the wheel. Pretthe entire slide 11 and the rotating o? the spindle 20 are suitably counterhted in the usual manner. This may convi iiently be done by providing a chain attached to slide 13 and passing over wheel to counterweight 42 provided at the opposite end of the chain and enclosed within the column l1.

To rotate the spindle 20 and wheel 21 a t. .111 puley is provided of sulticient width to permit engagement with the drivling; belt 51 when the slide 13 is in any position to which may be adjusted.

The driving; connections for the spindle 920 and also for the work table comprise main driving pulley 6O driven from any suitable source of power by a belt 61. Proferably the pulley is rotatably mounted on the main driving; shaft 62 by ball-bearings G3 and is provided with an integral. flange 64. 'lilze outer surface out flange 6% is in the term ot a cone and is adapted to fit in driving}; contact with a corresponding conicul sud o formed on a pulley 65. lt is by tliis pulley 5-5 that belt 51 is driven.

the spindle 20 and rotating parts so that tween pulley 60 and toe drum pulley 50 to belt 51' passes over idler pulleys 60 convenien mounted at the rear of column 11 to properly guide the belt 51. Pulley 65 is suitablysprinted to the shaft 62 by key 66 into shat G2, the pulley 65 being slidable alon shaft 62 over this hey. i

.ft 6? which is preterably mounted in ball-bearings 59 is provided with shoulder 67 again t which a collar (58 is to be retained. Adjacent the colo8 helical spring 69 surrounding the shaft 692 which at its opposite end presses against a shoulder formed in the bore of pulley 65. Preferably the spring 69 is on.-

tirely enclosed within an extension of the pulley 65. At the outer end of the pulley extension 70 is a circumferential groove 71.

A; hort shaft 72 mounted adjacent the groove 71 in pulley 65 is provided with a yoke member, one part of which is shown at 73 having suitable pins 74; engaging within the groove 71 provided in extension 70. Normally the parts are held by spring 69 in the position shown in 4i but oscillation f shaft 72 by means of a suitable lever 75 serves to compress spring 69 and thus moves the pulley 65 out of contact with the driving pulley 60 and thus stops its rotation. To hold the lever 75 in its inoperative position a latch 75" is provided having; a notch 76 into which the lug 77 on lever 75 may fit.

To rotate the table 100 the following mechanism is provided which is preferabl operated from the shaft 62 which is used also for rotating the spindle 20. it. clutch member 80 is rotatively mounted on the shaft 62 and coupled therewith are gears 81. and 82 preferably of different diameters. These three parts may conveniently be rig);- idly secured together as shonoi. Adjacent the clutch. member 80 is a corresponding clutch member 83 splined to the shaft 62 by key 84: set rigidly in the shaft 62, the clutch member 88 being slidable along shaft 6:2 over this key 84. Normally the clutch mem ber 83 is held incontac't with the clutch member 80 by means of acoil spring 85 surrounding the shaftv 62 and at one end bearing against the shoulder 67 provided on this shaft. The opposite end of spring S5 presses against an extension to the clutch member 83. Normally the parts are held in the position shown in Fig. 4;, in which position the gears 81 and 82 are rotated with the shaft 62. A short shaft 86 is provided. having); yokes 86" at the ends of arms 87" (but one being shown) engaging a ball-bearing: 87 mounted in a depression formed in the clutch member 83. Oscillation of the shaft 86 by means of the treadle 87 moves the clutch member 83 out of contact with clutch member 80 and therefore stops the rotation of these gears 81 and 821 one of which during the operation of the machine is in gagement with its mating To hold the treadle 87 in its downward position a suitable latch 87 is provided.

Lying parallel, with the shaft 61% and ad'- jacent thereto is a-shaft 90 rotatable within suitable bearings 91. provided in the frame 10. This shaft carries gears 92 preferably made integral with each other and of different diameters, and adapted to mate with 81. and 82 respectively when the are in either extreme position on shaft 90. Gear member 9:2 is slidable along shaft 90 over a key: 93- setinto this shaft. The position shown in Fig. l is the neutral position for gear member 92 in which the shaft 90 is not rotated, rotation of the shaft 90 at different speeds being accomplished by sliding the gear member 92 to engagement with either ar 81 or gear 82. in order to vary the potion of this gear member 952 it is only neccssary to oscillate the lever 95 which is at tached to a shor v shaft in engagement with the slidinggear 92 by an appropriate yoke enclosing ogears 92 (not shown).

in Fig. 3 is shown a vertical central section of the rotating; work table, the driving means for this table being shown in this figure and Fig. 4:. At is shown a chuck preferably of the magnetic type carried at the upper end of the shaft 101 this chuck iforn'iingthe rotating table. This shaft 101 comprises the driving means for the work table and is preferably bolted securely to the lower surface ofthe work table or chuck 100 by screws 102 passing through a flanged portion 103. provided at the upper end of shaft 101.

The chuck 100 shown in Fig. 3 on its lower surface is provided with an insulating ring 100 in which are embedded the slip rings 101" adapted to be connected to the electric circuit within the body of the chuckitself. Contact brushes (not shown) mounted di rectly below tie rings 1.01 and connected to a source of electric current are adapted to contact with the outer exposed faces of the rings 101*.

As is usual in this class of machines the chuck and work to be ground are flooded with water .30 prevent them from becoming overheated. This water may be supplied through conduits to a position on the chuck outside the abrasive wheel or to a point on the chuck within the abraidiny; ring of the wheel. in Figs. 1v and 3 I show both. couduits one or both of which may be used simultaneously. At 56 is shown a conduit. in which is provided a controlling valve 57 extending to a point on the chuck outside the wheel 21 and at 58 another conduit extcnding upward through the frame of the machine to a point on the chuck within the periphery of the wheel. Preferably the conduit 58 is made vertically adjustable as shown. The conduit 58 within a supply pipe 55f and may be if: stened therein in any adjusted position by clamping screw 58 ft is to be understood that any form of a chuck may be utilized in connection with this machine but I prefer to use a magnetic chuck as shown which provides a convenient means for holding the piece or pieces to be ground in place and permits rapid removal and replacement of these articles.

For convenience in promptly stopping the rotation of the chuck 100 when it is desired to measure or remove the articles being ground a friction brake is provided as shown in Fig. 1. This may conveniently be opershaft 101.

ated by means of the treadle 87*. At the time the trcadle 87 is depressed to throw out the clutch 83 a reach arm 88 attached at one end to the treadle arm 87 is also depressed forcing a short arm 89, acting as a. brake shoe, against the periphery of the chuck 100.

At the lower end of the shaft 101 is a bevel gear 104; suitably fastened by any convenient means to this shaft and meshing with another bevel gear 105 mounted on an extension shaft 90" at the forward end of driving shaft 90 and normally in alignment therewith. The driving shaft 90 is provided with a bearing 91 in the base'or frame of the grinding machine as above described and between the bearing 91 and the extension shaft 90 it is provided with a flexible link or coupling 106 to enable the extension 90 and the driving shaft 90 to be tilted slightly out of alignment with each other. J Between the coupling 106 and the pinion 105 is a suitable bearing 10'? for this extension shaft 9O which is mounted on and may be tilted with a table mounting 110. Preferably an outer bearing 108 may be provided for the forward extension shaft 90 of the driving shaft 90 just forward of the pinion 105, this hearin also provided in table mounting 110.

Any suitable flexible coupling may be provided between shaft 90 and extension shaft 90, the one hown comprising two identical members 109 in the form of short bars keyed respectively to shaft 90 and extension shaft 90. Bars 109 are set at right angles to each other and have fastened thereto a plurality of disks 109 of flexible material such as leather. With shaft 90 and extension shaft 90 slightly out of alignment rotation of these shafts may take place by slightly flexing the disks 109 Shaft 90 in its bearings 91 may slide forward to compensate for the tilting of the extension shaft 90.

During the operation of loading the chuck 100 with articles and especially when alarge number of small articles are to be placed on the chuck to be ground simultaneously, it is convenient to rotate the chuck 100 in one direction independently of the shaft 90 and change speed gears 81 and 82 above de scribed. T his mechanism may comprise any form of clutch permitting operation of the driven member in one direction independently of its driving means but preferably 1 use a spring-pressed roller 77 retained in the body of bevel gear 104-. The shaft 101 is provided with a bushing 78 keyed in any convenient manner to the lower end of this This bushing 78 is provided" with a depression 79 for the roller 77 which is pressed in one direction by suitable springs at one side of the roller 77. The action of this roller 77 is to permit the shaft 101 to be rotated in one direction when the shaft 90 is not rotating but will allow the shaft 90 when rotating to positively drive the shaft 101 and chuck 100. w

The table mountingdlO above referred to is preferably mounted in bearings 111 to oscillate about the transverse shaft 112 and this mounting 11.0 and the table or chuck 100 may be adjusted in any oblique position about the axis of this shaft 112 within a small angle by means of adjusting screw 115 mounted rigidly in a carriage 120 presently to be more fully described in which the mounting 110 is carried. Preferably, I provide a suitable knurled and graduated nut 116 about this adjusting screw 115, the graduations indicating the degree to which the table 110 has been tilted. A suitable locking nut 117 and washer 118 are provided on the screw 115 to hold the table 110 in adjusted position. An additional adjustment of the table mounting is permitted in addition to the angular adjustment above described; this is to move the chuck 100 transversely toward or away from the spindle 20.

The table mounting 110 is mounted in a carriage 120 provided with a suitable groove engaging a tongue 123 upstanding on the upper surface of the frame in order to permit forward and rearward sliding of the chuck 100 and mounting 110 in relation to the wheel 21 and the spindle 20. To hold the carriage 120 in adjusted position relative to the axis of the wheel spindle 21 a screw 121 is provided which may conveniently be provided, as shown in this figure, with a pair of collars 122 near its head end. These collars enclose between them a milled portion provided on the head 124: of the adjusting screw 115 as above described. The threaded end of screw 1.21 extends into the frame or bed of the machine.

From the above described construction it will be seen that the carriage 120 may be adjusted directly toward. or away from the wheel 21 within a limited distance. In the usual position of the chuck or table 100 its center is in alignment with the outer periphery of the abrasive wheel, but the adjustment above described is provided so that the center of the table 100 may be varied to more or less overlap the periphery of the wheel. The tilting of the table 100 by adjustment of the nut 116 permits the abrasive wheel to grind a slightly dished or converted article.

The table or mounting 110 is provided with an annular flange 130 completely enclosing the work table 100 and at its rear end extending high enough, as shown at 131. to enclose the grinding wheel. 20. Pivoted in this flange 130 by means of bolts or screws 132 is a guard 133 of substantially annular form which is shown in Fig. 3 in operative worm wheel 150.

position by full lines and in its inoperative position assumed when loading the machine by dotted lines. 1 preferably provide a spring-pressed catch or latch which fits under and holds the movable guard 133 in its upper or operative position. It will be seen from this construction'that by simply pulling the knob 136 of the catch 1.35 the guard 133 may be dropped at its outer or forward end by pivoting about the axis of bolts 132, thus permitting ready access to the chuck 100 for the purpose of removing and resettting the articles to beground.

The device for controlling and adjusting thevertical position of the wheel 21 comprises, as above mentioned, a pinion 17 mounted on a short shaft 18 suitably mounted in the column 11 of the machine and which is in mesh with the rack 16 provided on the wheel slide 18. The shaft 18 extends outwardly at one side of the frame and is provided on its outer end with a worm gear fastened thereto in any suitable wayyas by a key as shown. Rotatively mounted on the end of shaft 18 and preferably enclosing gear 150 is a. lever 151, one arm 152 of which is extended to form a handle and the arm 153 extending oppositely therefrom including a yoke 154perinitting the lever 151 to be definitelypositioned relative to slide 13 and locked in. this fixed position by means of clamping bolt 155 mounted on the body or frame of the machine. Also mounted on this arm 153 oflevcr 151 is a contact button 156 which bears against a suitably hardened plate 157 adjacent the clamping bolt 155 on the column 11.

From this construction thus described. it will be seen that the lever 151 can be securely locked in. one position relative to the column 11.. By rotating the worm wheel150 and the pinion 17 the grinding wheel 21 may be very slowly raised or lowered in relation to the work table or chuck 100; also by looseningthe clamping bolt 155 the lever 151 may be rotated about its axis thus rotating the gear150 and pinion 17 so that the wheel 21 is rapidly raised or lowered. I

In order to slowly and gradually rotate the worm wheel 150 and pinion 17 in relation to the lever 151 the iiollowing mechanism is provided. Transversely mounted in the lever 151 near its axis is a short worm shaft 160 carrying a worm 161 pftlftblttbly made integral with shaft 160 and in mesh with the At one end of this'worm shaft 160 is-provided a suitable hand wheel 162 by means of which the shaft 160 and the gear 161 may be rotated. This hand wheel 162 provides a convenient and readily accessible means for gradually moving the wheel slide 18 and wheel 21 vertically in re lation to the worm while the lever 15]. is locked in position.

At the opposite end of the worm shaft 160 is fastened a bevel gear which is in mesh with a bevel pinion 171 mounted on or made integral with a short cross shaft 172 arranged at right angles to the worm shaft 160. This cross shaft 172 carries at its outer end a suitable pair of handles 173 which prefer ably are mounted on a plate 17%. The ratio between the gears170 and 171 is about three or four to one, so that by rotating the plate 17 1 a speed of rotation is given the gear 150 of about one fourth that of rotationyof the hand1e'162. This latter mechanism may be conveniently used to adjust the spindle 20 to ompensate for wearing away of the wheel 21 and for fine'feed adjustments.

0n the plate 1741 I preferably provide a series of graduations as shown at 175. These are so calibrated that rotation of the plate 174 between adjacent graduations indicates a vertical movement of the wheel 21 of one thousandth of an inch.

From the above description the operation of the machine may be obvious but a short description will be given. With the Wheel slide-12) elevated and the guard member 133 lowered to the position shown in dotted lines in Fig-3 the chuck is ready to be loaded with the articles-to be ground. As soon this loading operation is completed the wheel slide 13 is lowered by means of the lever 151 which may be then looked in position by means of locking belt 155. As soon as the movable guard 133 has been raised so that it may engage the latch 135 and the water supply turned on to llood the table 100 and the articles to be ground with water the grinding may be begun.

The wheel 21 may be advanced to grind the articles placed on chuck 100 by means of hand wheel 162, the distance advanced by the wheel 21 being indicated by the graduations 175 on plate 174. The machine may also be used and ordinarily would be used when'a large number of identical articles are to be ground by operation of lever 151 to feed the wheel 21 against the articles to be ground. Iirthis case the position of the lever 151 relative to the position of the slide 13 is adjusted or varied by means of the handle 73; this adjustment however would only have to be varied as theabrasive wheel 21 became more and more worn. In this case as soon as the lever 151 is brought to a position in which the button156 is in contact with plate 157 the wheel is definitely positioned relative to the chuck 100.

The contact button 156 and the contact plate 157 have no tendency to wear or change their positions so that this stop arrange ment permits the slide 13 to be repeatedly brought down toward the chuck 100 tothe same position within a very minute variation and this may be accomplished by merely rotating the pinion shaftlfl by the arm 152 on lever 151. As soon as the lever 151 has been rotated so that the contact button 156 and contact plate 157' touch each other continued pressure on the lever 151 can. have no effect on the position of the slide 12. Any

pressure applied to the lever 151 serves merely to slightly deflect the arm 15;}, the effect of which on the work is not appreciable.

It will thus be seen that a convenient, rapid and accurate method of control for the abrasive wheel has been provided which permits rapid and precise grinding of duplicate articles or which is adaptable to a wide range of sizes and types of articles to be ground.

as soon as the articles have been ground to the desired dimension the slide may be raised by means of lever 151 and the table 100 may be stopped by movement of clutch 83 operated by foot treadle 87. Simultaneously with the movement of clutch 83 the brake shoe S9 is applied against the pe riphery of chuck 100, thus bringing'the chuck 100 promptly to rest. The guard 133 may then be lowered to its inoperative position by movement of the latch 135, thus permitting ready access to the table 100 by the operation to remove the articles ground and for placing other articles in position ready for grinding.

lVhat I claim is:

i. A wheel adjusting and feeding means for surface grinding machines comprising in combination, a wheel slide, a lever for op erating said slide, and means to vary the position of said lever relative to said slide.

2. A Wheel adjusting and feeding means for surface grinding machines comprising in combination, a wheel slide, a lever for op crating said slide, means to definitely position said lever relative to said slide, and means to vary the position of said lever relative to said slide.

3. A wheel adjusting and feeding means for surface grinding machines comprising in combination, a Wheel slide, a lever for operating said slide, and means mounted on said lever to vary the position of said lever relative to said slide.

at. A wheel adjusting and feeding means for surface grinding machines comprising in'combination, a wheel slide, a lever for operating said slide, and means enclosed by said lever and adjacent its fulcrum to vary the position of said lever relative to said slide.

5. ll. wheel adjusting and feeding means for surface grinding machines comprising in combination, a wheel slide, a lever for operating said slide, and a worm and worm wheel to vary the position of said lever relative to said slide.

6. A Wheel adjusting and feeding means for surface grinding machines comprising in combination, a wheel slide, a lever for operating said slide, means to vary the position of said lever relative to said slide, and an indicator on said last mentioned means to indicate the position of said slide relative to said lever.

T. A wheel adjusting and feeding means for surface grinding machines comprising in combination, a wheel slide, t lever for operating said slide, and a worm mounted on said lever in engagement with a worm wheel to vary the position of said lever relative to said slide.

8. A wheel adjusting and feeding means for surface grinding machines comprising in combination, a wheel slide, a lever for operating said slide, and a Worm mounted on said lever and in engagement with a worm wheel, said wori'n and worm Wheel being enclosed by said lever to vary the position of said lever relative to said slide.

9. A wheel adjusting and feeding means for surface grinding machines comprising in combination, wheel slide, a lever for operating said slide, means to vary the position of said lever relative to the slide, and an indicator on said lever, the axis about which said indicator rotates being parallel to the axis about which said lever may rotate.

10. A wheel adjusting and feeding means for surface grinding machines comprising in combination, a wheel slide, a lever 1o tatable about a horizontal. axis for operatsaid slide, means to vary the position of said lever relative to the slide, and an indicator on aid lever, the axis about which said indicator may rotate being parallel to the axis about which said lever may rotate.

11. ii. wheel adjusting and ii'eeding means for surface grinders comprising in combina-- tion, a wheel. slide, a lever for operating said slide, a worm and worm wheel mounted on said lever to vary the position of said lever relative to said slide, and an indicator connected with said worm.

12. A. wheel adjusting and feeding means for surface grinders comprising in combination, a wheel slide, a lever for operating said slide, a worm and worm wheel mounted on said lever to vary the position of said lever relative to said slide, and supplemental means on said lever to rotate said worm.

18. A. wheel adjusting and feeding means for surface grinders comprising in combination, whee slice, a lever for operating said slide, a worm and worm Wheel mounted on said lever to vary the position of said lever relative to 'd slide, and motion reducing means on. said lever to rotate said worm.

A .LTe

wheel adjusting and feeding means for surface grinders comprising in combination, a wheel slide, a lever for operating said slide, a worm and worm wheel mounted on said lever to vary the position of said lever relative to said slide, and a pair of bevel gears on said. lever to rotate said worm.

15. A wheel. adjusting and feeding means for surface grinders comprising in combination, a wheel slide, a lever for operating said slide, a worm mounted on said lever in engagement with a worm wheel to vary the position of said lever relative to said slide, motion reducing means on said lever to rotate said worm, and an indicator mounted on said motion reducing means.

16. A wheel adjusting and feeding means for surface grinding machines comprising in combination, a wheel slide, means for operating said slide, a lever rotatable about said operating means, means to clamp said lever to the frame of the machine, and means in engagement with said lever to operate said slide operating means to raise and lower said slide.

1'7. A wheel adjusting and feeding means for surface grinding machines comprising); in combination, a wheel slide, rack and pinion means for operating said slide, lever ro tatable about said operating means, means to clamp said lever to the frame of the machine, and means in engagement with said lever to operate said slide operating means to raise and lower said slide.

18. A wheel adjusting and feeding means for surface grinding machines comprising in combination, a wheel slide, means for oper ating said slide, a lever rotatable about said operating means, means to clamp said lever to the frame of the machine, and means comprising a worm and worm year mounted in cooperative relation with. said lever to operate said slide operating means to raise and lower said slide.

1.9. A wheel adjusting and feeding means for surface grinding machines comprising in combination, a wheel slide, rack and pinion means for operating said slide, a lever rotatable about said operating means, means to clamp said lever in a definite position relative to the frame of the machine, and means comprising a .worm and worm gear mounted in. cooperative relation with said lever to operate said slide o iierating means to raise and lower said slide.

20. A wheel adjustii'u; and feeding means for surface grinding machines comprising in "combination, a wheel slide, means for operating said slide comprising a lever n'rhereb g' the slide may be rapidly elevated or lowered, means to clamp said lever to the frame of the said machine, and means on said lever to slowly raise and lower the slide.

21. A table mounting for surface grinding machines comprising in combination, a horizontally pivoted table mounting, a vertical shaft extending thcrethrough, driving means therefor, a flexible coupling between said shaft and driving means, and means to adjust said table mounting to variable oblique positions.

A table mounting for surface grinding n'iachines comprising in combination, a horizontally pivoted table mounting, a vertical shaft ext nding therethrough, driving means therefor, a flenible coupling between said shaft and driving means, means to adjust said table mounting to variable oblique positions, and means to adjust said table mounting transversely.

A tablemounting for surface grinding machines con'iprising in combination, a movable "arriage, a table mounted thereon, a chuck rotatably mounted in said table, means to i said table relatively to said carriage, dining means for said table, and a flexible co nection in said driving means to permit tilting of said table.

A table mounting for surface grinding machines comprising in combination, a movab e carriage, a table mounted thereon, a eh ucl; rotatabl mounted in said table, means to tilt said table relatively to said carriage in a horizontal axis, driving means for said table, and a flexible connection in said driving means to permit tilting of said table.

25. A. table mounting for surface grinding machines comprising in combination, a mow able carriage, a table mounted thereon, a chuck rotntably mounted in said table, means to tilt said table relatively to said carriage, change speed driving means for said table, and a flexible connection in said driving means to permit tilting of said table.

26. A. table mounting for sitirface grinding machines comprising in combination, a slidably m unted carriage, a table mounted thereon, a chuck rotatably mounted in said table, means to tilt said table upon said carriage about a horizontal axis, driving means for table, and a flexible connection in said driving means to permit tilting of said table.

97. A surface grinding machine comprising in combination, a wheel supporting column, a abrasive wheel. adiustably mounted thereon, a carriage movable toward and away from said column, a table on, said carriage, and means permitting oblique adjust-- ment of said table.

A surface grinding machine comprising in combination, a wheel supporting column, an abrasive wheel adjustably mounted thereon, a carriage movable toward and away from said column, a table mounting on said carriage, said mounting being angularly ady, stable, and a work holding table carrier by said mounting.

29. A surface grinding machine COIllPPlS- ing in combination, a wheel supporting 001- umn, an abrasive Wheel adjustably mounted thereon, a carriage movable toward and away from said column, a table mounting on said carriage, said mounting being angularly adjustable about a horizontal axis, and a Work holding table carried by said mounting.

30. A surface grinding machine comprising in combination, a Wheel supporting column, an abrasive wheel mounted thereon, a carriage movable toward and away from said column, a table mounting on said carriage, said mounting being angularly adjustable, and a rotatable Work holding table carried by said mounting.

31. A surface grinding machine comprising in combination, an abrasive Wheel, a Work table, means for operating said table, a guard enclosing said Wheel and table, and means permitting vertical movement of a part of said guard into and out of operative position.

32. A surface grinding machine comprising in combination, a vertically mounted abrasive Wheel, a Work table, means for rotating said table, a guard surrounding said Wheel and table, and means permitting vertical oscillation of a part of said guard into and out of operative position.

33. A surface grinding machine comprising in combination, a vertically mounted grinding Wheel, a Work table, means for rotating said table, a guard surrounding said Wheel and table, means permitting a part of said guard to be tilted about a horizontal pivot means from operative position into a position for loading said table, and a springpressed latch for normally holding said guard member in operative position.

34. A surface grinding machine comprising in combination, a vertically mounted abrasive Wheel, a Work table, means for sup porting said table, and an extension to said last mentioned means forming a portion of a guard surrounding said table, said extension having connected thereto a member forming a movable guard surrounding said table.

35. A surface grinding machine compris ing in combination, a vertically mounted abrasive Wheel, a Work table, means for sup porting said table, and an extension to said last mentioned means forming a portion of a guard surrounding said table, said extension having horizontally pivoted thereto a member forming a movable guard surrounding said table.

36. A surface grinding machine comprising in combination, a vertically mounted abrasive Wheel, a Work table, means for supporting said table, an extension to said last mentioned means forming a portion of a guard surrounding said table, said extension having connected thereto a member forming a movable guard surrounding said table, and means to detachably hold said movable guard in operative position.

37 A surface grinding machine compris ing in combination, an abrasive Wheel, a work table, means for operating said table, a guard enclosing said wheel and table, and means normally holding a movable portion of said guard in operative position, move ment of said holding means permitting said movable portion to drop to inoperative position.

38. A surface grinding machine comprising in combination, an abrasive Wheel, a Work table, means for operating said table, a guard enclosing said Wheel and table, and means normally holding a movable portion of said guard in operative position, movement of said holding means permitting said movable portion to tilt about a horizontal axis to inoperative position.

39. A surface grinding machine comprising in combination, an abrasive Wheel, a Work table, means for operating said table, a fixed guard enclosing said Wheel, a movable guard member attached thereto, and means normally holding said movable guard member in operative position, movement of said holding means permitting said movable guardmember to drop to inoperative position.

40. In a surface grinding machine, rotatable Work table, driving means therefor, and means permitting rotation of said Work table in one direction independently of its driving connections.

41. In a surface grinding machine, a rotatable Work table, change speed driving means therefor, and means permitting rotation of said Work table in one direction independently of said change speed driving means.

42. In a surface grinding machine, a rotatable Work table, gear driving means therefor, and means comprising a clutch permitting rotation of said table in one direction independently of its driving connections.

48. In a surface grinding machine, a rotatable Work table, gear driving means therefor, and means comprising a clutch contained Within one of said driving gears permitting rotation of said table in one direction independently of said driving means.

44:. In a surface grinding machine, a rotatable Work table, change gear driving means therefor, including a pair of bevel gears, and means comprising a clutch contained Within one of said bevel gears permitting rotation of the table in one direction independently of said driving means.

45. A surface grinding machine comprising in combination, a Work holding table, means for rotating said table, a clutch in said driving means a brake adapted to engage said table, means to move said brake 10 gage said table, and means to move said into operative position simultaneously with brake into operative position simultaneously movement of said clutch out of operative With movement of said clutch out of opera position, and means to hold said clutch out tive position. of operative position.

46. A surface grinding machine compris- In testimony whereof, I hereunto afiix 16 ing in combination, a Work holding table, my signature. means for rotating said table, a clutch in said driving means, a brake adapted to en- CARROLL KNOVLES. 

